Answered: Confused about this behavior

I'm just starting to look at Sencha Touch and I downloaded the code base and the SDK. I used the 'sencha generate app' command to build the default application and it worked fine. I then tried to make a simple change and got an odd result.

In the default implementation of the sample app, the second 'tab' contains a video and is defined like this:

The only difference was using the list instead of the video xtype. When I ran the application and visited the second tab, I saw the title bar, but no list items. However, if I changed my code to do this:

the list appeared. Going back to my first modification, I inspected the page and found that the list items were actually rendered, but one of the outer containers had a height of 0 which was preventing the items from being displayed. Is there something else I should have done in my configuration to make things work properly or is there a bug in Sencha Touch?